Preheat oven to 180°C. Grease 20cm round tin and set aside.
Sift together the flour, cocoa, salt, baking powder and soda. Set aside.
Mix the water, oil, vinegar, mashed avocado and vanilla and mix well. Add the sugar and mix well again. Pour the wet mixture into the bowl of your stand mixer and using a low speed (4-6) add in the flour gradually and mix till smooth. Remove and pour into baking tin. (If you want to make it a layered cake, divide the batter into 2 pans. Bake for 30-40 minutes or till a tester comes out clean.
Butter cream frosting
115g cream cheese
2 tbsp lemon juice (optional)
1 cup icing sugar
Using an electric mixer, mix the cream cheese and butter till light and fluffy. Add the lemon juice and the sugar (gradually) and mix till well incorporated. Remove and chill till you’re ready to ice the cake.